Gas mixer



y 1935- r s. P. JONES 2,000,901

GAS MIXER Filed Feb. 19, 1934 Q 0 I I I l i I A I I Q I INLET J77 m6)" 1 F .55 771a 645M157 Z 1 4/ l Patented May 14, 1935 GAS MIXER Sam P. Jones, Dallas, Ten, assignor of forty per cent to E. W. Schadek, Dallas, Tex.

Application February 19, 1934, Serial No. 711,954

6 Claims.

This invention relates to new and useful improvements in gas mixers.

One object of the invention is to provide an improved gas mixer for gas engines, whereby more eflicient air and gas mixing is provided and smoothness of operation is assured.

Another object of the invention is to provide a gas mixer arranged so that the piston coacts with a continuous shoulder which prevents an accumulation of dirt and dust on said piston and relieves the spring from shearing off such accumulations in closing the piston when the engine is stopped.

A further object of the invention is to provide means for shifting a normally free sliding piston into intimate contact with the housing wall contiguous to the gas inlet port, when the engine is stopped, whereby gas leaks are prevented.

Another object of the invention is to provide an improved gas mixer for a gas engine which is so arranged that the supply of air drawn therethrough is determined by the suction of the engine, said suction of the engine also drawing in a correct amount of gas in proportion to the air supply at the same time. 7

Among other objects are; the provision of an amplified gas opening upon the initial operation of the gas mixer to enrich the air-gas mixture, thus making for quick and easy starting; also simple construction, which provides for easy cleaning; and accessibility of parts.

A construction designed to carry out the invention will be hereinafter described, together with other features of the invention.

The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawing, in which an example of the invention is shown, and wherein:

Figure 1 is a side elevation of a gas mixer constructed in accordance with the invention, showing the piston closed and throttle closed,

Figure 2 is a vertical sectional view of the same, showing the piston and throttle in their closed positions,

Figure 3 is a partial vertical sectional view of the same, showing the piston open,

Figure 4 is a view at right angles to Figure 1, partly in elevation and partly in section,

Figure 5 is a view in elevation, similar to Figure 4, showing the piston open,

Figure 6 is an underside view,

Figure 7 is a horizontal cross-sectional view taken on the line 'I| of Figure 3,

Figure 8 is a horizontal sectional detail showing the constantly open air intake and the cleaning shoulders, and

Figure 9 is a horizontal cross-sectional view taken on the line 9-9 of Figure 5.

In the drawing the numeral l0 designates the gas mixer housing Whl. has a general cylindrical shape and may be made in one piece of suitable metal. The usual attaching flange II is provided at the upper end of the housing. A cylindrical bore l2 extends axially through the housing. Certain portions of the housing wall may be reduced in thickness to save material and weight, but this is optional.

In the upper or neck portion of the housing a butterfly throttle valve I3 is journaled in the bore, as is usual. On one of the trunnions H, which extends through the housing wall, is fastened a throttle lever l5 provided with a stop l6 and a set screw I! for engaging a stud l8 on the housing and limiting the opening and closing of the throttle, as is the practice in this art.

The bottom of the housing wall is routed out to form an annular recess or channel IS in which is mounted a cap plate 20 in the form of a circular disk. The plate is somewhat less in diameter than the channel and is loosely and rotatably confined in said channel by a pair of screws 2 I.

A piston or piston valve 22 is mounted to slide vertically in the bore l2 of the housing. The piston has a stem 23 which extends through the plate and receives a coiled spring 24 confined thereon by a washer 25 and a key 26. The spring bears against the bottom of the plate and holds the piston in its closed position. This spring resists the upward movement of the piston, acting in opposition to the suction of the engine, closing the piston when the engine is stopped.

The piston is provided with a rectangular gas port 2'! having an offset opening or recess 28 at the upper corner of one end. Above the gas port the piston is formed withan annular air opening or slot 29. This air slot is one of the features of the invention and. is continuous except for narrow webs 30 which are. cut back from the piston surface, so as not to contact the bore l2 and to provide a continuous annular shoulder 3| at the top of said slot'and a like shoulder 32 at the bottom of said slot.

Air inlet ports 36 extend outwardly through the wall of the housing. A nipple 31 is provided on the housing for receiving the gas supply pipe 38 and within the nipple a rectangular gas inlet port 39 is formed. This port has flares I at each end in the bore l2 (Figures 4 and 8).

By cutting back the webs 30, any dust or dirt which may accumulate thereon will not interfere with the operation of the piston. If the webs were flush with the surface of the piston any dust accumulation thereon would have to be sheared ofi as the piston is slid vertically; It is obvious this disadvantage is overcome for the set back webs permit easy and eflicient operation regardless of dirt or dust thereon.

The gas ports 21 and 39 are of equal height and the air slot or port 29 and air inlets 36 are also of equal height. The air openings and gas opening are spaced the same distance from each other in both the piston and housing, consequently both are opened in proportion to each other. In other words, when the air slot begins to register with the air inlets 38, the ports 21 and 39 come into registration. It is noted that when the gas ports first register, the recess 28 at the upper corner of one end of the gas port 21 will admit more gas, making for a richer mixture at starting and slow speeds.

When the engine is stopped the spring 29 which is under tension, as is shown in Figures 3, 4 and 5, will pull the piston downwardly to its closed position, as is shown in Figures 1 and 2. In order to effectually close the gas port 39 and prevent gas leakage, the piston 22 is given a loose sliding fit in the bore l2, so that it may have a limited lateral movement. A wedge key 4| is formed integral with the plate 20 and engages in a complementary slot 42 in the piston. When the piston is pulled downwardly by the spring it is shifted laterally by the key, which is located diametrically opposite to the port 39.

This brings the solid wall of the piston into intimate contact with the wall of the bore surrounding the gas port, thereby sealing off said port. It is noted that when the piston is in its lowered position, it is resting on the wedge shaped key 4|, there being a space provided between the head of the piston and the top of the cap plate. Therefore, it is assured that the key will positively act to displace the piston laterally each time said piston is lowered.

The cap plate 20 has a hand lever 43 extending radially through an arcuate guide 44 in the wall of the channel [9, whereby said plate may be rotated and through the instrumentality of the key 4|, rotate the piston. This shifts the gas ports 21 and 39 circumferentially of each other and varies the quantity of gas admitted. It is pointed out that the flares 49 at each side of the port 39 are substantially the length of the gas port 21 in the piston so that when said piston is rotated, the port will register with said flares to admit a maximum of gas through the port. This adjustment, however, is rarely used, for under normal conditions the port 21 is positioned as shown in the drawing with relation to the flares.

In operation, the throttle valve I3 is opened. The suction of the engine, not shown, will pull the piston 22 upwardly causing the air slot 29 to begin to register with the air inlets 36. At the same time the upper end of the gas ports 21 will register with the lower end of the gas port 39. Due to the large area of the slot 29 and inlets 36, it is clear that a desired amount of air may be drawn in by the motor. Thus, the suction of the motor determines the supply 01' air. The gas ports are of such size that when the piston raises to permit the desired supply of air to be drawn in by the motor, the correct proportion of gas to that amount of air is admitted through the gas ports. Similarly as the motor gains speed the suction becomes greater, raising the piston further to admit more air and gas into the carburetor. It is pointed out that the suction of the motor at all times determines the air supply, said suction drawing only the required amount of air. The gas is admitted proportionately to the air supply.

It will be seen that due to the recess 28 at the upper corner of the port 21, more gas is admitted when the port 21 first registers with the port 39 than at a later point, thus making for a richer mixture at starting and slow speed. By providing this richer mixture when the engine is cold, the efficiency of operation is increased, as well as making for easy starting of the engine.

The description which has been given recites more or less detail of a particular embodiment of the invention which is set forth as new and useful; however, I desire it understood that the invention is not limited to such exact details of construction, because it is manifest that changes and modifications may be made, within the scope of the appended claims, without departing from the spirit of the invention.

What I claim and desire Patent, is:

1. A gas mixer comprising, a housing having gas and air inlets, a piston loosely slidable in said housing and having gas and air inlets located to register with the inlets of the housing when the piston is slid in said housing, and means for shifting the loose piston laterally oi the vertical axis of the housing to seal off the gas inlets when the piston is moved to a closed position.

2. A gas mixer comprising, a housing having gas and air inlets, a piston loosely slidable in said housing and having gas and air inlets located to register with the inlets oi the housing when the piston is slid in said housing, and means for automatically shifting the loose piston laterally of the vertical axis of the housing to seal off the gas ports when the piston is moved to a closed position. I

3. A gas mixer comprising, a housing having gas and air inlets, a piston loosely slidable in said housing and having gas and air inlets located to register with the inlets of the housing when the piston is slid in said housing, and means diametrically opposite the gas inlets in the housing and piston for shifting the loose piston laterally of the vertical axis of the housing to seal 01! the gas inlets when the piston is moved to a closed position.

4. A gas mixer comprising, a housing having gas and air inlets, a piston loosely slidable in said housing and having gas and air inlets located to register with the inlets of the housing when the piston is slid in said housing. said piston having an inclined slot at its lower end, and an inclined key arranged to engage in said slot for shifting the loose piston laterally of the vertical axis of. the housing to seal oh the gas inlets when the piston is moved to a closed position.

5. A gas mixer comprising, a housing having gas and air inlets, a piston loosely slidable in said housing and having gas and air inlets located to register with the inlets of the housing when the piston is slid in said housing, a cap plate closing the lower end of the housing and mounted to rotate, and means carried by said plate engaging the loose piston for shifting the same laterally of the vertical axis of the housing to seal oii the gas inlets when said piston is moved downwardly, said means also rotating the piston circumferentially within the housing to adjust the gas into secure by Letters lets with relation to each other when the cap plate is rotated.

6. A gas mixer comprising, a housing having gas and air inlets, a piston slidable in said housing and having gas and air inlets located to register with the inlets of the housing when the piston is slid in said housing, a cap plate closing the lower end of the housing and mounted to rotate, and means carried by said plate engaging the 10 piston for shifting the same laterally to seal oil the gas inlets when said piston is moved downwardly, said means also rotating the piston circumi'erentiallywithin the housing to adjust the gas inlets with relation to each other when the cap plate is rotated. said gas inlet in the housing being provided with flares, the length of which are substantially the length of the gas inlet in the piston, whereby a maximum of gas is admitted when the piston is moved'circumterentially to register the latter gas inlet with said flares.

8AM P. JOKE. 

